Improvement in sheathing and coating- ships  bottoms



V106. ooMPosmoNs,

COATING OR PLASTIC.

JOHN SCOFFERN,OF FINSBURY, ASSIGNOR TO HENRY BEAUFORT SEARS OF LIVERPOOL, ENGLAND.

Letters Patent No. 86,104, dated anuwry 19, 1869.

IMPROVEMENT IN SHEA'IHING- AND COATING- SHIPS BOTTOMS.

The Schedule referred to in these Letters Patent and making part of the same.

To all to whom it may concern:

Be it known that I, Jenn ScoFrnR-N, of 21 New North street, Finsbury, in the county of Middlesex, England, M. 13., a subject of theQueen of Great Britian, have invented or discovered new and useful Improvements in Sheathing Ships Bottoms, and other surfaces exposed to the action of sea-water, and I, the said JOHN SOOFFERN, do hereby declare the nature of the said invention, and in what'manner the same is tobe performed, to be particularly described and ascertained in and by the following statement thereof; that is to say- My process consists in the application, to ships bottoms and sides, and to other surfaces exposed to the action of sea-water, of certain materials, hereinafter to sire to limit the term paint, as hereinbcfore stated,

to a semi fiuid holding a true oil as an integral component.

I will commence, by describing what I will call a preferential paint, by which is to be understood a paint that I consider answers better than any other for my subsequent operations, inasmuch as this paint holds copperized ammonia, or, rather, a product of the evaporation of copperized ammonia, as an integral part. The preparation of this copperized ammonia I will describe, notwithstanding that this body is already known, and its manufacture I do not, in this specification, claim to have been discovered by me.

Oopperized ammonia, or (as some have denominated,

though not, I believe, in accordance with chemistry,)

copper-ate ofammonia, is the blue result occurring when liquor of ammonia has been brought into contact with copper surfaces, in the presenceof atmospheric air, and allowed to remain in contact for av considerable time. and any amount of copper, provided it be in excess of the ammonias solvent power. The time of steeping or exposure varies with circumstances, but I consider six weeks to be an average time; whether more or less, is of no consequence, provided the result be eiiicient, and this may be known by testing.

The bestitest I know of depends upon appreciation of the remarkable fact, that oopperized ammonia, in good order, rapidly dissolves woody matter, and, still more rapidly, silk. Supposing, then, I desire to know whether a specimen of copperized ammonia be in good order for the preparation of either my preferential paint or certain semi-fluid sheathing-bodies, hereinaf- By preference, I use ammonia of .880,.

ter to be described, and not coming within the category of paints, or the final laying on'o'f paper or textile sheathing-surfaces, I adopt thefollowing test:

Having poured a convenient quantity of copperized ammonia (say half a pint) into a wide-mouthed stopper-bottle, of at least one pint capacity, I add thereto a test-quantity of one-quarter of a yard of thin white Persian silk. If, on agitation, the silk wholly and absolutely dissolves,'within one minute, I conclude the copperized ammonia is adapted to all my purposes; if more than one minute he required, I conclude it not to be perfected, and that longer steeping of copper in contact with ammonia, with access of atmospheric air, is needed.

This is the best test of efficiency I know of. Specific gravity, for present purposes, I consider fallacious.

The fact is, however, that prolonged experience with copperized ammonia will place an intelligent operator beyond the need of using any testappearance s, not

possible't'o describe, affording a suflicient guide.

Having described this copperate of ammonia, I will now explain its application, in the manner which I prefer, to the manufacture of my preferential paint.

The materials employed are linseed oil, India rubher, and @pperiged ammonia. Td be precise, I will as'ume matte imperial gallon of linseed-oil is to be operated on. Having turned this quantity of oil into a capacious boiler of iron or copper, (it must not be of zinc,) I add thereto one pound avoirdupois of India rubber, and boil until the latter iswholly dissolved. I then add one imperial pint of copperized ammonia, little by little. The commotion is very violent, and the addition must. be made with care. I then boil until the last traces of ammonia, as indicated by the smell, have escaped. I then allow the whole to cool, and use it as a vehicle for holdingany such bodycolor as a painter may desire.

Having described the process of manufacturing this, my preferential paint, I will next describe the mode of preparing certain adhesive semi-fluid sheathingmaterials, necessary wholly or in part to my process. These said adhesive semi-fluid sheathing-materials I do not call paints, nor the operation of laying them on, painting, inasmuch as no oil proper, or fatty acid, in union with glycerine, enters into their composition.

For the sake of precision, I will individualize those hitherto used in my sheathing-process, by the numbers from 1 to 8. I

No. 1. Marine, glue and liquor of ammonia, of .880 specific gravity, of each equal weights, to be digested in contact with copper, in a closed vessel, to which atmospheric air may be admitted from time to time, agitating occasionally until solution be complete. The result will have the consistence of thick black paint. It is to be observed that I use marine glue in this case for convenience. The materials of marine glue will lead plaster,) and one part ammonia of No. 2, and allow to dry.

answer equally well. It is to be further observed that instead of letting the preparation of copperized ammonia go on simultaneously with its further solvent power-onmarine glue, copperized ammonia, already prepared, may be employed, and to the saving of some time; but whetherammonia or already-made copperized ammonia, surfaces of metallic copper should always be super-added.

No. 2. The same mingled with white arsenic. The proportions I find to answer best are, six parts, by weight, of the aforesaid black adhesive matter, and one part, by weight, of white arsenic.

No. 3. The same as No. 1, pitch being substituted for marine glue.

No. 4. The preceding arsenicalized.

No. 5. The same as No. 1, rosin being substituted for marine glue.

No. 6. The preceding arsenicalized.

No. 7 Two parts, by weight, of lead soap, (ordinary I preceding strength, the whole treated exactly as No.

No. 8 is the same arsenicalized.

Having described the preparation of my preferentialpaint, and theadhesive sheathing-matters, not to be called paints, (inasmuch as-they do not contain oil proper,) I will now go on to explain their use in my .process of marine sheathing.

First, as regards iron ships, the circumstances are such that processes for proteotingiron bottoms have .to be performed under many varying conditions.

The ship may be quite new, and the time atthe operators disposal practicallyunlimited. The ship may be old and worn, may have been subjected to painting or smearing, by compounds unfavorable to my treatment; may be laid up in a graving-dock for the smallest available time, whereby the-sheathing or painting-operator'is hurried; V

Again, theduration and direction of a voyage will have to be consulted. A ship destined forOalcutta will need less protection, for example, than one destined for Bombay.

Assuming an iron' ship to be perfectly new, I first lay on two coats of my preferential paint, or rather paint-vehicle, mingled with any convenient body-color. I prefer red lead.

A prejudice lies against this material, because of a prejudicial chemical action'sometimes set up. There can be no chemical action, however, so long as the paint is dry, and my subsequent processes of sheathing keep it dry. I

As soon as the second coat of paint has firmly set, I lay upon it sheets of paper, linen, or calico, either of which has been steeped in copperized ammonia, in good condition, for about one minute, a time sufficient to have promoted surface-solution of the materials steeped,

and to bring about adhesion, when the applied sheet has been rubbed down by a pad of linen, calico, Ol-(l2t0lll3- chouc.

This vegetable sheathing will dry hard and adhere firmly.

Upon convex and 'plane surfaces it always sticks tightly. From concave surfaces it may separate by the shrinkage of drying, if not slit at intervals, more or less frequent, according to the abruptness of the concavity; but what I prefer is, to treat. concave surfaces by a special modification of my process, which is the following Upon the painted surface, I smear one coat of either of'my adhesive sheathing semi-liquids, by preference, When dry, I smear another layer of the same, and to this, whilst wet and ammoniacal-smelling, I apply, by pressure and rubbing, sheets of paper, calico, or linen, that have already been steeped, for about a minute, in copporized ammonia, withdrawn and allowed to dry. They will adhere perfectly.

Sheets of paper. or woven vegetable material will desquamate under the action of sea-water, just as copper desquainates.

For the majority of voyages, they need no reduplication or covering. 7 I usually recommend, however, a

finish of one of the sheathing semi-liquids,- numbered from 1 to 8. p A brush, not of bristles, but of vegetablev fibre, is best adapted for laying'on these sheathing-glazes. T

I have here to repeat that my preferential paint, though best adapted to mysheathing-process, is not indispensable. Any ordinary paint I can operate upon, provided it really be paint, that is to say, a compound made up of body-color and a true drying-vehicle, such as a realoil, with or without turpentine.

Many, I may state mostyof the so-called marine paints are chemically regarded, and, according to the scientific chemical limitation, no paints at all; theyare merely greasy, permanently-moistsmears.

Upon surfaces such as these, I cannot lay either my sheathing, semifluid, adhesive bodies, or my sheetsheathing successfully. I

Upon a dry coating of any ordinary paint, I can operate'as follo'ws:

Although sheets of paper or woven vegetable material that have been immersed in copperized ammonia for-the time specified, and withdrawn, will not stick with any practical efficiency to'ordinary paint, they will stick with efficiency to a surface of any one of my sheathing, adhesive semi-liquids, laid on dry ordinary paint. Herein lies the solution of the problem. It remains to be observed that either of my sheathing, adhesive semi-liquids, from 1 to 8, may be laid on an iron surface directly, if such surface be neither acid nor greasy, understanding, by grease, fatty or oily mat ter, not having the quality of drying.

Although I have hitherto treated only of the application of my process to iron ships, yet it is ap licable to wooden ships. It is also applicable to the c veii'ng of other surfaces; for example, iron, copper, or yellow metal, of iron-bridge work. In short, the portion of my sheathing-process which has reference to the laying on of either of my sheathing, adhesive fluids, can

be applied to any surface, however irregular, and even the portion which relates to the laying on of paper or woven sheets can be applied to surfaces having considerable irregularity of outline.

I would observe that the fullest development of my sheathing-process is made up of the following stages:

' First. Painting either. by my preferential paint, or else some true paint, as already defined.

Second. The laying on of one or more of my copperized. ammonia sheathing semi-fluidsif the paint used has not been my preferential paint.

Third. The laying on of paper or woven tissue sheets by one of the two processes already described.

- Fourth. The sheathing not to be confounded with painting with one of my specified sheathing, copperized semi-fluids.

Nevertheless, the operation may be stopped at any stage, according to the amount of protection desired.

Having stated how my process is conducted, and described how the materials used in this process are to be manufactured, it is to be understood that considererable variations may be permitted in the proportions of ingredients used.

I have statedthe proportions which I consider best, not limiting myself thereto, but claiming the general application of copperized ammonia to the purpose of sheathing ships bottomsand other surfaces exposed to the action of water.

mo. soorrnmv.

Witnesses:

J OHMDEAN Both of N0. 17 Graceclmrch Street, London.

T. L. Wsnnnn, 

